<template>
  <div id="root">
    <div class="todo-container">
      <div class="todo-wrap">
        <!--        把方法传递给myheader-->
        <MyHeader :addTodo="addTodo"></MyHeader>
        <!--      把数据传递给list          把方法传递给list-->
        <list :todos="todos"></list>
        <MyFooter :todos="todos" :check-all-todo="checkAllTodo" :clear-all-todo="clearAllTodo"></MyFooter>
      </div>
    </div>
  </div>
</template>

<script>


import MyHeader from "@/components/MyHeader";
import List from "@/components/List";
import MyFooter from "@/components/MyFooter";


export default {
  name: "App",
  components: {MyFooter, List, MyHeader},
  data() {
    return {
      // todos:[
      //   {id:"001",title:'抽烟',done:true},
      //   {id:"002",title:'喝酒',done:false},
      //   {id:"003",title:'烫头',done:true},
      // ],
      //当不能获取数据，数据为null时，就用空数组
      todos: JSON.parse(localStorage.getItem("todos")) || []
    }
  },
  methods: {
    //从MyHander接收回todo存入data
    addTodo(todo) {
      this.todos.unshift(todo);
    },
    //从item接收到修改的id 更改其done值
    checkTodo(id) {
      this.todos.forEach((todo) => {
        if (todo.id === id) {
          todo.done = !todo.done;
        }
      })
    },
    //接收要删除的id，过滤之后重新赋值给todos
    deleteTodo(id) {
      this.todos = this.todos.filter(todo => {
        return todo.id != id;
      });
    },
    //全选or取消全选
    checkAllTodo(done) {
      this.todos.forEach(todo => {
        todo.done = done;
      })
    },
    //清除所有已经完成的todo
    clearAllTodo() {
      this.todos = this.todos.filter(todo => {
        return !todo.done;
      })
    }
  },
  watch: {
    todos: {
      //开启深度监测，监测todos包括todos里面的数据
      deep: true,
      handler(value) {
        localStorage.setItem('todos', JSON.stringify(value))
      }
    }
  },
  mounted() {
    //监听事件
    this.$bus.$on('checkTodo',this.checkTodo)
    this.$bus.$on('deleteTodo',this.deleteTodo)
  },
  beforeDestroy() {
    this.$bus.$off('deleteTodo')
    this.$bus.$off('checkTodo')
  }
}
</script>

<style>
/*base*/
body {
  background: #fff;
}

.btn {
  display: inline-block;
  padding: 4px 12px;
  margin-bottom: 0;
  font-size: 14px;
  line-height: 20px;
  text-align: center;
  vertical-align: middle;
  cursor: pointer;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 1px 2px rgba(0, 0, 0, 0.05);
  border-radius: 4px;
}

.btn-danger {
  color: #fff;
  background-color: #da4f49;
  border: 1px solid #bd362f;
}

.btn-danger:hover {
  color: #fff;
  background-color: #bd362f;
}

.btn:focus {
  outline: none;
}

.todo-container {
  width: 600px;
  margin: 0 auto;
}

.todo-container .todo-wrap {
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 5px;
}
</style>
